3D scene orientation indicator system with scene orientation change capability

ABSTRACT

The present invention is a system that provides an orientation indicator graphical user interface element in a display view of a three-dimensional scene. The orientation indicator can be used to automatically change a view of the scene to a predetermined viewpoint. The indicator includes view direction indicating controls that when activated cause the view of the scene to change to a view direction indicated by the control. The direction can be indicated by a shape of the control, such as by a cone with a point pointing in the direction of the view, or by the location of the control, such as being located on a marked scene axis of the indicator. The view of the scene is also automatically adjusted at the view position to center an object of interest in the scene and zoomed in/out to fit the object to the display view. The indicator is part of the three-dimensional scene and moves with the scene as the scene is manipulated by a user, such as in tumbling the scene. The indicator is held at a fixed position and size in the display view, such as in a corner of the display view, by moving the indicator about within the scene and changing the size of the indicator.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is directed to a widget or graphical userinterface (GUI) element that depicts three-dimensional (3D) sceneorientation and includes direction indicating controls that allow a userto orient a view of the 3D scene to align with the direction indicatedby the selected control and, more particularly, to a GUI element that isresident within the 3D scene, stays aligned with the scene as the sceneis tumbled by the user, remains in the same position and at the samesize in the display as the view changes, and has controls thatautomatically rotate the scene to a predetermined view when selectedwhere a scene object is centered in the display and sized to fit thedisplay.

2. Description of the Related Art

In the three-dimensional (3D) graphics art where computers are used toperform animation, 3D modeling and other tasks in which a 3D scene isdepicted, it is important to orient the user to the view into the sceneand to allow the user to easily change the view into the scene.Conventional interfaces 10 in the 3D art, such as shown in FIG. 1, caninclude an orientation gnomon 12 located in a display associated with a3D scene 14. As the view changes, the gnomon in the display is adjustedto reflect changes in the view into the scene. The gnomon can also belocated in the center of the scene or at the origin of the axes of the3D scene. This gnomon cannot be used to change a view of the 3D scene.

What is needed is a gnomon that can be used to change a view of a 3Dscene.

When a user wants to change the view of a scene, such as depicted inFIG. 1, to a particular desired view, the user can manipulate (tumble,rotate, translate, etc.) the scene to get the desired view. However, theuser must be particularly aware of the current view and themanipulations needed to get to the desired view. This can be difficultif the view has been tumbled a number of different times along complextumbling pathways. The user can also change the view to a desired viewamong a number of predefined views using a menu as depicted in FIG. 1.FIG. 1 depicts a pending selection of a back view. The menu selectionview change process requires that the user move through a number ofdifferent menu levels (3 in this example) to make such a selection,which takes time that may be considered wasted. However, even whenprovided with such a menu, the menu selection needed to get the desiredview based on the current view is often not readily apparent especiallyto an unsophisticated user.

What is needed is a system that provides the user with orientationinformation and selectable controls for view manipulation that do notrequire a complex selection process and that visually guide the user toa desired view with directional aids associated with the selectioncontrols.

SUMMARY OF THE INVENTION

It is an aspect of the present invention to provide an in scenethree-dimensional orientation indicator that automatically remainsaligned with the orientation of a three-dimensional (3D) scene.

It is an additional aspect of the present invention to provide anin-scene indicator that remains positioned at a predetermined positionin the display and at a predetermined size in the display as the sceneis manipulated into different views by the user.

It is another aspect of the present invention to provide the indicatorwith controls or buttons that can be used to change the view of thescene.

It is also an aspect of the present invention to provide the orientationindicator with direction indicators associated with the controls thatindicate the direction of the various views that can be selected.

It is a further aspect of the present invention to automatically centerand fit the objects in the 3D scene to the display view subsequent to aview change.

The above aspects can be attained by a system that provides anorientation indicator graphical user interface element in athree-dimensional scene where the orientation indicator can be used toautomatically change a view of the scene to a predetermined viewpoint.The indicator includes controls that when activated or selected causethe view of the scene to change to a view direction indicated by thecontrol. The view direction associated with a particular control can beindicated by a shape of the control or by the location of a control. Theview of the scene is also automatically adjusted at the selected viewposition to center an object of interest in the scene in the displayview and to fit the object to the display view. The indicator is movedabout within the scene and changed in size to position the indicator ata predetermined fixed position in the users display view and at apredetermined fixed size.

These together with other aspects and advantages which will besubsequently apparent, reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawings forming a part hereof, whereinlike numerals refer to like parts throughout.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a conventional 3D display with a menu for selecting aview of a scene to be displayed.

FIG. 2 depicts a view compass or GUI element according to the presentinvention.

FIG. 3 shows a view compass in a 3D scene.

FIGS. 4-7 illustrate changes in view of a scene and correspondingchanges in the view compass.

FIG. 8 illustrates a handle/control of the compass being highlighted asa cursor passes over the handle.

FIG. 9 illustrates the orientation after the handle highlighted in FIG.8 has been selected.

FIG. 10 is a flowchart of the process performed when a control of thecompass is selected.

FIGS. 11-17 illustrate additional embodiments of the present invention.

FIG. 18 illustrates hardware of the present invention

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention is a graphical user interface (GUI) orientationindicator element indicating the orientation of a three-dimensional (3D)scene that has directional buttons or controls that allow theorientation to be changed to align a display view of the scene with thedirection indicated by a selected button. The invention can be called aview compass GUI element, tool or widget or just a view compass.

The view compass 30, as depicted in FIG. 2, is a collection of sevenvirtual buttons or handles 32-44, represented as a 3D figure (widget) ona computer display. The buttons are conventional virtual buttons in thatthe operating system user interface recognizes that an action is to betaken when a cursor is on one of the buttons and a mouse button isactivated or “clicked”. The compass 30 becomes or is an element of a 3Dscene, such as those used for modeling, CAD, or videogames. These sevenbuttons or controls 32-44 provide shortcuts for moving the virtualcamera in (or viewpoint of) the scene to pre-defined positions.

The view compass 30 is unique in that its position is coupled to thevirtual camera or the point of view into the 3D scene as established byan associated system, such as the Alias ImageStudio™ system, making italways available in the same place. The orientation of the compass 30 islocked to the orientation of the virtual 3D world, so that the action ofeach view-changing handle is visually obvious. This is a change fromcurrent ways of switching views in 3D software, as discussed above, thatrequire the user to mentally calculate (or guess) which absoluteposition they need to switch to in order to get the view they want.

The view compass 30 is drawn as a 3D figure, comprising a core handle(or control) 44 with six handles (or controls) 32-42 arrangedperipherally around it (one handle on either side in each of the X, Y,and Z directions). The compass 30 preferably has a form, as depicted inFIG. 2, that allows most or all of the handles to be visible (andtherefore pick able) at any given time. For Alias ImageStudio™ we prefera cubic core 44 with cone-shaped handles 32-42, but many other forms arepossible as will be discussed later herein. Preferably, the entirevisible portion of a cone is a control.

The preferred compass 30, as noted above, includes cone shaped handles32-42 where the point 46 of the cone preferably points in the directionof the virtual camera view point, which provides a visual and somewhatintuitive information about what view will be provided when the handleis selected. The compass 30 preferably also has some additional visualcues. One of the handles, in this case handle 44, is a different colorto mark it as the “front” direction of the scene, and the system canlabel the positive X, Y, and Z axes associated with the handles (seeFIG. 14). These refinements are not required to make the view compasswork well, but are preferable additions.

There are a number of aspects of the view compass 30 that it isimportant to understand. The first is how the compass 30 it behaves inthe scene since it is part of the scene. As the scene view is changedthe compass 30 changes with the scene. For example, as the scene istumbled, because the compass is in the scene, the compass 30 alsotumbles with the scene automatically maintaining an orientation thatmatches the orientation of the scene. However, as the scene is tumbled,the compass would normally move within the display view or virtualcamera view of the scene provided to the user. As another example,because the compass is part of the scene, if the user zooms into thescene, the size as well as the position of the view compass 30 would beexpected to change in the display image or display view presented to theuser. The present invention preferably maintains the compass in the sameposition (preferably a display corner) and at the same size, as will bediscussed in more detail below. A second aspect is how the displayedscene changes when a handle of the compass is selected. When a handle isactivated the scene is switched to the viewpoint of the handle, the 3Dscene object is centered and the display view is resized (zoom-in orzoom-out) so that the object fits within the display as will discussedin more detail later herein.

At all times, the view compass 62 is preferably drawn in the view 64that it controls. Its position and size are fixed relative to thevirtual camera (and in terms of the number of pixels on the computerdisplay, preferably about 110 by 110 pixels), but the compass 62orientation is fixed relative to the 3D world coordinate system, as canbe seen in FIG. 3. This way, as the camera moves, the view compass 62stays constantly at one size, in one out-of-the-way corner of the screen(upper right in FIG. 3). In this position, it also tumbles to match theorientation of the virtual world (note that the front position pointsalong the axis of the ring in FIG. 3). When the computer redraws thescene, the view compass 62 is preferably drawn last so that it is drawnon top of everything else in the scene. This ensures that the compass 62is always visible, even if scene objects come between the compass 62 andthe virtual camera. (Depending on the details of the particular graphicssystem being used, it may be necessary to turn off the z-buffer, orensure that the compass is just past the near clipping plane.)

Set forth below is pseudo-code for an algorithm that can be implementedin a preferred graphic system in a language, such as C++, and thatplaces the view compass 62 at a fixed position and size, while allowingit to rotate with the world axes. // Information required for thisprocedure: // point cameraPosition; // 3d position of the virtual cameravector cameraDirection; // normalized vector in the direction of viewvector cameraUp; // normalized vector pointing “up” in camera-spacevector cameraRight; // normalized vector pointing “right” incamera-space angle viewAngle; // horizontal angle of the view frustum ofthis camera angle viewAngleV; // vertical angle of the view frustum ofthis camera int viewportWidth; // width of the screen display in pixelsint viewportHeight; // height of the screen display in pixels const intcompassSize; // size of the view compass in pixels const intcompassOffset; // offset of the view compass center // from the cornerin pixels procedure drawViewCompass( camera, viewport ){ // calculatethe width/height of the viewing frustum at // one unit in front of thecamera // float frustumWidth = 2.0 *sin(viewAngle*0.5)/cos(viewAngle*0.5); float frustumHeight = 2.0 *sin(viewAngleV*0.5)/ cos(viewAngleV*0.5); // calculate the width of apixel at a distance one unit in front // of the camera // floatpixelSize = (frustumWidth/viewportWidth); // calculate the size of thecompass in real-world units // setCompassSize( compassSize * pixelSize); // calculate the position of the compass center //setCompassPosition( cameraPosition + cameraDirection +((frustumWidth*0.5)−(pixelSize * compassOffset)) * cameraRight +((frustumHeight*0.5)−(pixelSize * compassOffset)) * cameraUp); // Noneed to set the orientation; it's always aligned with the // world. Wecan now draw the compass at the appropriate position, // size, andorientation. . . .

The process set forth above starts by calculating how big the viewcompass would have to be in 3D space to maintain the same apparent sizein pixels on the current display. This can change based on the focallength of the virtual camera, or on the size of the window in which theprogram is running. Next, the process calculates where in 3D space theview compass would need to be located in order to maintain the sameapparent position relative to the camera. Once that is done, the compasswidget itself can be drawn in a conventional way.

The process discussed above is executed each time the user changes theviewpoint of the scene, such as by tumbling, rotating, translating, etc.the scene. This is depicted in FIGS. 4-7, which show a user tumbling theview from a perspective view (FIG. 4) to an offset top view (FIG. 5),then to an upside down view (FIG. 6) and finally to a left side view(FIG. 7). In FIG. 4, the front cone of the compass 62 is pointingperspectively in alignment with the axis of the ring scene object 66 inthe scene 64. FIG. 5 shows the compass 62 also in the same corner andthe same size as in FIG. 4, even though the ring appears to have becomea bit larger while the compass 62 has also been tumbled to keep thefront cone aligned with the ring axis and in the relative front positionof the ring 66. FIG. 6 again shows the compass 62 in the upper righthand corner at the same size and tumbled to be in alignment with thescene 64. FIG. 7 depicts the view compass 62 in a left side view alignedwith the ring 66, so that the front cone points in the axial directionof the ring 66.

In addition, the above discussed compass move and resizing process isexecuted each time the user changes the viewpoint of the scene byselecting one of the controls of the view compass as discussed below.

As discussed above, each handle of the view compass 72 acts as a buttonor control. As a cursor passes over each handle, as depicted in FIG. 8,the handle is conventionally highlighted in the scene 74 to show thatthe handle will be picked if the user clicks-on or selects the handle.When the user clicks-on one of the cone handles, the camera moves toalign its view direction with the axis of the cone as depicted in FIG.9. (That is, the camera turns around the scene to point the same waythat the cone points.) After the click in FIG. 8, the camera is nowlooking along the same axis as the clicked handle, down the center ofthe ring 76 in the scene 74, and the screen is filled with the object ofinterest (the ring 76 in this example) as shown in FIG. 9. The viewcompass 72 has the same relative position and size in the scene 74, buthas rotated to a new orientation, matching the worldview. Once inselected orientation, the virtual camera or display view is repositionedso that objects of interest in the scene are centered and made to fitinto the view, as shown in FIG. 9. The objects of interest depend on theapplication. For example, the view compass could focus on selectedobjects, or on all objects. The camera, as shown in FIG. 9, alsoswitches from a perspective to an orthographic mode. When the userclicks-on or selects the center handle or core (see 44 of FIG. 2) of theview compass, the camera rolls to a predefined view such as the apredefined perspective view, such as the home view depicted in FIG. 8.Again, the camera adjusts its position to ensure that all objects ofinterest are made to fit into the view. The operations of the softwarethat controls how the compass behaves will be discussed in more detailbelow with respect to FIG. 10.

The flowchart of FIG. 10, for convenience, depicts a process 90 that issequential. However, when implemented in an object-oriented language,such as the preferred C++ language, the tasks may be distributed intoobjects that may not be sequentially organized. Before any selection ismade, a conventional operation (not shown) highlights any handle overwhich the cursor passes and the process waits 92 for a selection. Wherea selection is preferably first processed by the compass behaviorsoftware described herein. If the cursor is used to make a selection,such as by clicking a button on a mouse or engaging a key on a keyboard,the process leaves the wait state 92, and a determination 94 is made asto whether the selection, cursor click-hit, is a selection of a controlof the view compass. If not, the selection event is passed 96 to othersoftware of the system. If so, a determination 98 is made as to whichhandle or control has been hit. If the top handle is selected (hit), theview or virtual camera is conventionally rolled or tumbled 100 todisplay the top view to the user. If the bottom handle is selected(hit), the view is conventionally rolled 102 to display the bottom view.Likewise for the left (104), right (106), front (108) and back (110)views. When the home or core control is selected, the view provided tothe user is rolled 112 to the perspective view. The system thenconventionally centers 114 the object of interest and fits the displaysize to the object as previously discussed. Next, the view compass sizeand position are adjusted 116 in the 3D scene to place the compass inthe desired predetermined position at the predetermined size. The systemthen returns to await another input event.

The view compass of the present invention can have a number of differentshapes or other features that allow the direction of the view to bevisualized, that depict the orientation and that are easy to select. Thecone shaped controls of FIG. 2 can be pyramid shaped. Arrows can besubstituted for the cones. FIG. 11 depicts a compass 130 with axialindicators 132, 134 and 136 for the xyz axes. FIG. 12 illustrates acompass 150 where balls 152 are the controls and the links 154 betweenthe balls 152 indicate view direction. That is, the stick of the balland stick combination points at the core indicating view direction. FIG.13 shows a compass 160 where the views are indicated by planes orwindows 162. The direction of the view is indicated by the location ofthe window and by the view through the window to the core. FIG. 15 showsa compass 180 with view bookmarks 182, 184 and 186 that indicateadditional system or user created views to which the system can alignthe scene when selected. These additional views can be used for specialpurposes, such as in modeling where people often want to “bookmark”certain views, that is, save them because they contain an attractiveangle for rendering, or because they are focused on a particular detailthat they want to work with, and need to get back to periodically. Or,the user may be saving views of particular interest to point them out toa colleague. Additional components or scene views markers associatedwith the view compass can be provided as depicted in FIG. 16. In thisembodiment, the view compass 200 has additional view markers, such as202, 204 and 206, arbitrarily located at segment boundaries of a gridplane and that cause the display view to align with the particular planeof the view marker when selected. The view markers of the presentinvention can also be exploded as depicted in FIG. 17 where the displayview 220 is of the entire 3D scene 222 and the markers or controls, suchas controls 224, 226 and 228 are located at the periphery of the scene.

FIG. 18 illustrates hardware of the present invention where the 3Dscene, including the view compass, is depicted on a display 250, such asa CRT, PDP or LCD. A computer 252, such as desk top computer, runs theprocesses of the present invention, along with the 3D graphics software,that allow the user to manipulate the scene and select controls on thedisplay, via input devices, such as a mouse 256 and keyboard 258. Otherinput devices can also be used, such as tablets, gloves, etc., thatallow a user to point at and select objects.

The system of the present invention also includes permanent or removablestorage, such as magnetic and optical discs, RAM, ROM, etc. on which theprocess and data structures of the present invention can be stored anddistributed. The processes can also be distributed via, for example,downloading over a network such as the Internet.

The present invention has been described with the visible part of eachcone being a control. It is possible to have a region around each conethat also acts as a control. The axis labels (x, y, z) can also be partof the controls. The present invention has been described as making afront cone a different color to indicate a front direction of thecompass and scene. It is possible to make a front face of the core 44 adifferent color either in addition to or as a substitute for thecoloring of the front cone. Iconic representations of the contents ofthe scene from the various points of view can also be placed on the corefaces.

It is also possible to use the compass as a tumbling tool such thatdragging a cone will turn the scene. It is also possible to drag animage, such as a texture, and drop it on a cone and have the systempaste the image on a part of the scene such as a wall.

The many features and advantages of the invention are apparent from thedetailed specification and, thus, it is intended by the appended claimsto cover all such features and advantages of the invention that fallwithin the true spirit and scope of the invention. Further, sincenumerous modifications and changes will readily occur to those skilledin the art, it is not desired to limit the invention to the exactconstruction and operation illustrated and described, and accordinglyall suitable modifications and equivalents may be resorted to, fallingwithin the scope of the invention.

1. A graphical user interface element, comprising: an orientationindicator associated with a three-dimensional scene and visuallyindicating an orientation of the scene, and comprising: view directioncontrols each indicating a direction of a corresponding view into thethree-dimensional scene and causing a display view of three-dimensionalscene to change to the corresponding view when selected.
 2. An elementas recited in claim 1, wherein an object in the scene is centered andsized to fit the display view when a scene change occurs responsive toselection of one of the controls.
 3. An element as recited in claim 1,wherein the indicator is part of the three-dimensional scene, alwayspositioned at a predetermined position in the display view and alwayssubstantially a same size in the display view.
 4. An element as recitedin claim 1, wherein the element comprises: a central core controlassociated with a perspective view of the scene; and axial controlsperipherally positioned with respect to the core control, aligned withthe axial dimensions of the scene and associated with correspondingfront, back, top, bottom, left side and right side views.
 5. An elementis recited in claim 4, wherein the front direction control is differentfrom the other controls.
 6. An element as recited in claim 4, whereinthe axial controls are each shaped to point at the core controlindicating the view direction of the axial control.
 7. An element asrecited in claim 4, further comprising a non-axial control peripherallypositioned with respect to the core control and indicating a directionof a corresponding view into the three-dimensional scene and causing adisplay view of three-dimensional scene to change to the correspondingview when selected.
 8. An element as recited in claim 7, wherein thenon-axial controls are specified by a user.
 9. A process, comprising:determining whether a view direction indicating control of anorientation indicator in a display view of a three-dimensional scene hasbeen activated; and orienting the display view to the view direction ofthe control when the control is activated.
 10. A process as recited inclaim 9, wherein the indicator is in the three dimensional scene and theprocess further comprises: positioning the indicator in the scene toplace the indicator in a predetermined position in the display view; andchanging the size of the indicator in the scene to fix the indicator ata predetermined size in the display view.
 11. A process as recited inclaim 9, further comprising: centering a scene object in the displayview; and fitting the scene object to the display view.
 12. A system,comprising: display; an input device used to make selections on thedisplay; and a computer coupled to the mouse and the display, displayinga three-dimensional scene on the display in a display view, the scenecomprising an orientation indicator indicating the orientation of thescene, the orientation indicator comprising view controls indicating aview direction and the computer changing the display view to the viewdirection associated with a control selected by the mouse.
 13. Acomputer readable storage controlling a computer by a process storedthereon determining whether a view direction indicating control of anorientation indicator in a display view of a three-dimensional scene hasbeen activated and orienting the display view to the view direction ofthe control when the control is activated.
 14. A graphical userinterface having three-dimensional directorial indicators indicating anorientation of a three-dimensional scene and that orient the view to thedirection indicated when activated by a user.
 15. A graphical userinterface element, comprising: an orientation indicator associated witha three-dimensional scene, visually indicating an orientation of thescene, part of the three-dimensional scene, always positioned at apredetermined position in the display view and always substantially asame size in the display view, and said indicator comprising: viewdirection controls each indicating a direction of a corresponding viewinto the three-dimensional scene and causing a display view ofthree-dimensional scene to change to the corresponding view whenselected, the view direction controls comprising: a central core controlassociated with a perspective view of the scene and causing a displayview of three-dimensional scene to change to the correspondingperspective view when selected; axial controls peripherally positionedwith respect to the core control, aligned with the axial dimensions ofthe scene, associated with corresponding front, back, top, bottom, leftside and right side views, shaped to point at the core controlindicating the view direction of the axial control with the front viewdirection control being a different color than the other controls andthe axial controls being labeled with axial labels comprising part ofthe controls; and a non-axial control peripherally positioned withrespect to the core control by a user and indicating a direction of acorresponding view into the three-dimensional scene and causing adisplay view of three-dimensional scene to change to the correspondingnon-axial view when selected, and wherein an object in the scene iscentered and sized to fit the display view when a scene change occursresponsive to selection of one of the controls.